1998 GMC SIERRA maintenance

How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you may need to add some lubricant.
When the differential is cold, add enough lubricant to
raise the level to 1/2 inch (12
mrn) below the filler
plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom
of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in the Index.
Engine Coolant
The cooling s stem in your vehicle is filled with
DEX-COOL engine coolant. This coolant is designed
~
to remain in your vehicle for 5 years or 150,000 miles I
(240 000 km) whichever occurs first, if you add only ~
DEX-COOL’ extended life coolant.
8
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
i
with engine overheating, see “Engine Overheating” in 1
the Index.
A 50/50 mixture of water and DEX-COOL@ coolant will: 1
0 Give freezing protection down to -34°F (-37°C).
0 Give boiling protection up to 265 OF (1 29 O C).
Protect against rust and corrosion.
0 Help keep the proper engine temperature.
0 Let the warning gages work as they should.
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Brakes
Brake Fluid
Your brake master cylinder
reservoir is here. It
is filled
with DOT-3 brake fluid.
There are only two reasons why the brake fluid level
in the
reservoir might go down. The first is that the brake fluid
goes down to an acceptable level during normal brake
lining wear. When new linings are put
in, the fluid level
goes back up. The other reason is that fluid
is leaking out
of the brake system. If it is, you should have your brake
system fixed, since
a leak means that sooner or later your
brakes won’t work well, or won’t work at
all.
So, it isn’t a good idea to “top off’ your brake fluid.
Adding brake fluid won’t correct a leak.
If you add fluid
when your linings are worn, then you’ll
have too much
fluid when
you get new brake linings. You should add
(or remove) brake fluid,
as necessary, only when work is
done
on the brake hydraulic system.
- - -
4 CAU-ION:
If you have too much brake fluid, it can spill on the
engine. The fluid
will burn if the engine is hot
enough. You or others could be burned, and your
vehicle could be damaged. Add brake fluid only when
work is done on the brake hydraulic system.
Refer to the Maintenance Schedule to determine when to
check your brake fluid. See “Periodic Maintenance
Inspections” in the Index.
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Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does
not mean something is wrong with
your brakes.
Properly torqued wheel
nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque wheel nuts
in the
proper sequence to
GM specifications.
If you have rear drum brakes, they don‘t have wear
indicators, but if you ever hear a rear brake rubbing
noise, have the rear brake linings inspected immediately. Also, the rear brake drums should be removed and
inspected each time the tires are removed for rotation
or
changing. When you have the front brake pads replaced,
have the rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.
See “Brake System Inspection”
in Section 7 of this manual
under
Part C “Periodic Maintenance Inspections.”
Brake Pedal Travel
See your dealer if the brake pedal does not return to
normal height, or
if there is a rapid increase in pedal
travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc brakes
adjust for wear.
If your brake pedal goes down farther than normal, your
rear drum brakes may need adjustment. Adjust them by
backing
up and firmly applying the brakes a few times.
Replacing Brake System Parts
The braking system on a modern vehicle is complex. Its
many parts have to be
of top quality and work well
together if the vehicle is to have really good braking.
Your vehicle was designed and tested
with top-quality
GM brake parts. When you replace parts of your braking
system
-- for example, when your brake linings wear
down and you have
to have new ones put in -- be sure
you get new approved
GM replacement parts. If you
don’t,
your brakes may no longer work properly. For
example,
if someone puts in brake linings that are wrong
for your vehicle, the balance between your front and
rear brakes can change
-- for the worse. The braking
performance you’ve come
to expect can change in many
other ways
if someone puts in the wrong replacement
brake parts.
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4. Push in gently on the
bulb, turn it to the
left and remove it from
the socket. Windshield Wiper Blade Replacement
For proper type and length, see “‘Normal Maintenance 1 I
Replacement Parts” in the Index. I i
i
5. Put in a new bulb and, pushing in gently, turn it to
the right until it is tight.
6. Put the socket back in the lamp assembly and replace
the lens and lens seal.
To replace the windshield wiper blade assembly:
1. Lift the wiper arm and rotate the blade until it is
2. Push the release lever and slide the wiper assembly
3. Install a new blade by reversing Steps 1 and 2.
facing away from the windshield.
toward the driver’s side
of the vehicle.
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When to Check
Check your tires once a month or more. Also, check the
tire pressure of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t tell if your tires are properly inflated
simply by looking at them. Radial tires may
look
properly inflated even when they’re underinflated.
Be sure
to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
(10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires as soon as possible and check
wheel alignment.
Also check for damaged tires or
wheels.
See “When It‘s Time for New Tires” and
“Wheel Replacement” later in this section for more
information. If your vehicle has dual rear wheels, also
see “Dual Tire Operation” later
in this section. The purpose
of regular rotation
is to achieve more
uniform wear
for all tires on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services”
in the Index for scheduled
rotation intervals.
1
FRT FRT
[x[
If your vehicle has single rear wheels, always use one of
the correct rotation patterns shown here when rotating
your tires.
If your vehicle has front tires with different load ranges
or tread designs (such as all season vs. on/off road) than
the rear tires, don’t rotate your tires front
to rear.
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Finish Damage Chemical Paint Spotting
Any
stone chips, fractures or deep scratches in the finish
should be repaired right away. Bare metal will corrode
quickly and may develop into a major repair expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer or other service
outlets. Larger areas of finish damage can be corrected
in your dealer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust control
can collect
on the underbody. If these are not removed,
accelerated corrosion (rust) can occur on the underbody
parts such as fuel lines, ft-ame, floor pan and exhaust
system even though they have colrosion protection.
At least every spring, flush these materials from the
underbody with plain wate.r. Clean any areas where mud
and other debris can collect. Dirt packed in closed areas
of the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can do
this
for you.
Some weather and atmospheric conditions can create a
chemical fallout. Airborne pollutants can fall upon and
attack painted surfaces
on your vehicle. This damage
can take two forms: blotchy, ringlet-shaped discolorations, and small irregular dark spots etched into
the paint surface.
Although
no defect in the paint job causes this, GM will
repair, at no charge to
the owner, the surfaces of new
vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
This applies only to materials manufactured and sold by
General Motors. Bodies, body conversions or equipment
not made or sold by General Motors are not covered.
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Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are based on the latest information available at the time of printing,
and are subject to change. If a part listed
in this manual is not the same as the part used in your vehicle when it was
built, or
if you have any questions, please contact your GM truck dealer.
These specifications are for information only.
If you have any questions, see the service manual for the chassis or
refer
to the body manufacturer's publications.
VIN Code
Oil Filter';"
Air Cleaner Filter*
PCV Valve*
Spark Plugs*
Fuel Filter*
Wiper Blades**
Wiper Blade Type
Wiper Blade Length
w M
PF52 PF12 18.1
A 1300C??
A 1300C??
CV746C CV796C
4 1-932 4 1-932
GF626 GF626
22154886 22 154886
Trico Trico
18 inches (45.0 cm) 18 inches
(45.0 cm)
"AC part number
**GM part number
?Use
a PF52 oil filter if your vehicle has four-wheel drive.
??A1301C high-capacity air cleaner filter.
R J
PF1218? PF1218
A 1300C?? A 1300C??
CV796C cv774c
4 1-932 4 1-932
GF626 GF626
22 154886 22154886
Trico Trico
18 inches (45.0 cm) I8
inches (45.0 cm)
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Section 7 Maintenance Sch - dulp
This section covers the maintenance required for your vehicle. Your vehicle needs these services to retain its safety,
dependability and emission control performance.
7-2
7-4
7-5
7-5
7-6
7-7
Introduction
Part
A: Scheduled Maintenance Services
Short Trip/City Definition
Short Trip/City Intervals
Long Trip/Highway Definition
Long Trip/Highway Intervals 7-8
Short Trip/City Maintenance Schedule
7-28 Long Trip/Highway Maintenance Schedule
7-40 Part
B: Owner Checks and Services
7-44 Part C: Periodic Maintenance Inspections
7-46 Part
D: Recommended Fluids and Lubricants
7-49 Part
E: Maintenance Record
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